The provision of a stereoscopic (3D) user experience is a long held goal of both content providers and display manufacturers. Recently, the urgency of providing a stereoscopic experience to home users has increased with the production and tentative release of multiple 3D movies or other 3D material (e.g., concerts or documentaries).
To ensure rapid adoption among consumers, the ideal solutions should be those that can be implemented with minimal or no alteration to existing playback devices such as set-top boxes, DVD, and Blu-ray disc players, as well as existing 3D capable displays, such as digital light processing (DLP) displays by Samsung and Mitsubishi, some Plasma displays, and polarized based and frame sequential LCD displays.
One possible method for the delivery of 3D content that has these properties is the consideration of creating, coding, and delivering 3D video content by multiplexing the two views into a single frame configuration using a variety of filtering, sampling, and arrangement methods. Sampling could, for example, be horizontal, vertical, or quincunx, while an offset, e.g. a sampling offset, could also be considered between the two views allowing better exploitation of redundancies that may exist between the two views.
Similarly, arrangements could include side by side, over-under, line-interleaved, and checkerboard packing among others, as shown in FIGS. 1-6. Unfortunately, these methods do not provision for the delivery of full resolution stereoscopic material, which can impact quality and experience, and essentially can be an issue for many applications.
The desire for full resolution has lead to some systems that utilize two separate and independent bitstreams, each one representing a different view, like the simulcast 3D video delivery architecture shown in FIG. 8. Unfortunately, the complexity of this method, its bandwidth requirements, i.e. redundancies between the two views are not exploited, but also the fact that this method is not backwards compatible with legacy devices and can have considerable implications to the entire delivery system, has not lead to its adoption.
An extension of this method, that tries to exploit some of the redundancies that may exist between the two views was proposed and adopted as a profile of the Multiview Video Coding (MVC) extension of the MPEG-4 AVC/H.264 video coding standard, i.e. the Stereo High profile, that provisions for the encoding and delivery of stereoscopic material. An example of the MVC based 3D video delivery architecture is shown in FIG. 9. Redundancies are exploited using only translational motion compensation based methods, while the system is based on “intelligent” reference buffer management, i.e. in which order references from the base or enhancement layers are added in the enhancement layer buffer and considered for prediction, for performing prediction compared to the original design of MPEG-4 AVC. Unfortunately, even though coding efficiency was somewhat improved (i.e., 20-30% over simulcast), complexity issues, incompatibility with legacy devices (only 2D support is provided), and the not so significant performance benefits presented using such method still make it as a somewhat unattractive solution.